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New synthetic oil...

NAPA has come out with 2 new items, high mileage and sythetic. Both below the cost of it Valvoline brother...especially the synthetic at employee cost...need i say, $2.08 a QT....it retails for $3.99 (or was it $3.49?) It WAS on sale for $2.99....

Anyhow, who cares about the high mileage/valv max life, i think thats a crock of bull snit-sil.

So, this synthetic oil, which is supposidly made by Valvoline...woudl you guys trust it inplace of the real valv/mobil/castrol??? The mobil and castrol are both avalible to me as well...but only at $4.84 a QT, vs the walk in of $4.99...so thats rather expensive to keep pouring in my GL-10 everyday...it uses 1 QT every 100 miles...and since its about 50 mile to work, and 50 back...thats $5 a day! So...this NAPA Synth...what do ya'll think???

Now note that once I get the DL on the road, i could use the GL-10 as a test bed for this stuff, since the engine is going out anyhow...and just see how long it takes to finally quit. So far its run on Mobil 1 10W-30 synth for 21,000 miles...now its getting a fleet 15w-40 oil, Rotella T, for the time being...since its cheaper...but this NAPA is only 2 cents more expensive to me to use...

Yes, i have figured as much, since I work at NAPA. Packaging is the same and everything....its just that there is no where you can find that NAPA oil is related to the Valv company....unless you look at the MSDS (is that the abbrev?) safety sheets.

Anyhow, i just dont know much about the Valv synthetics. I used some valv. synth. racing oil one time...it seemed to do quite well...

The normal NAPA stuff seems sound as well. Otherwise, Ive never used valv. or NAPA oil reguarly to know...i figured there woudl be some opinions here to be found.

A rose by any other name would smell as sweet, but "synthetic oil" != (does not equal) "synthetic oil".

Just this last week, I attended a 3.5 hour lecture on PCMO (Passenger Car Motor Oils) and a section on modern coolant issues, put on by ChevronTexaco and hosted by Bob Nehren, Chevron Lubricants Training Specialist -- Hey, they give me a free dinner to attend, and I won a Leatherman knock-off as a prize for knowing the answer to one of his rhetorcial questions, so why not?

I'm an oil snob, won't use just anything if I have a choice, and I tried to pay attention to the lecturer's info, because it does pay to know more about this sort of thing.

Some high points:

Synthetic oil is man-made. Man-made from what? Ethane, if I recall correctly. That would be C2H6, I think. That's synth. oil base stock, and for decades its adavantage over non-synth is that it is very, very clean. Lube oil from 20 years ago was about 70% clean. Really. That's as clean as they could make lube oil from mineral base stock and still sell a product economically. Synth oil tech was around (since WWII) but it was expensive to produce the stuff, too expensive to sell for cars.

"Synthetic" oil for cars uses (used, see below) Poly Alpha Olefin (PAO) technology to provide the major benefits to the synthetic base stock.

Some premium and aviation synth. oils use organic esters (diesters, polyol esters) instead of PAOs. AMSOil falls into this category. It's more expensive than PAO tech.

Until about 3/4 years ago, the term "synthetic" would refer to oil intended for cars that used either (di)ester or PAO tech in its formulation.

Refining process categories have been established by the American Petroleum Instute (API). A good overview is at Chevron's site. Broadly, they are:
. Group I
Solvent Extraction method of refining. This method removes 50-80% of the junk in conventional distilling of lubricating oil. It uses solvents in two stages to remove aromatics and waxes from the base stock.

. Group II
Hydroprocessing method of refining. Uses three stages, primarily high pressure catalytic (hydrocracking), to convert incomplete carbon molecules to complete molecules (no weak bonds?), converts waxes to isoparaffins (isodewaxing), and uses no solvents. End product is 98%+ clean, with almost no aromatics, nitrogen, sulpher, and little impurities.

. Group III
Unconventional base oils, same as Group II except viscosity index is greater than 120.

. Group IV
Poly Alpha Olefins base -- see above. More expensive to produce than Group II/III, but less expensive to produce than (di)ester tech.

. Group V
Catch-all group. Everything else. This includes very cheesy oils, and also very high-quality oils including (di)esters.

BTW, Chevron invented modern hydrocracking/isodewaxing technology, and now 2/3rds of lubricating oil sold in the US uses their licensed refining technology.

Now.Group I oils is what we had for cars until about 1982 (except ATF, which has been a synthetic blend for over 40 years, I think). It's also what the cheap stuff you buy in Brand X (Say, Wal-Mart) bottles contains. About 70% clean, 80% from a the very best Group I refiners. Read the API "donut": do you see SL or CH-4 ratings? I didn't think so. Group I oil won't meet those specs even minimally.

Group II oils are the std oil that major brands -- all major brands -- are selling by 2004.

Group IV oils (synthetic, PAO) is what pretty much all volume "synthetic oil" used to be five years ago. ExxonMobil's Mobil1 is one example of a PAO Group IV synthetic.

Castrol was sued by ExxonMobil over the use of the term "synthetic" several years ago, because Castrol's Syntec, which had been a PAO oil, was later changed to being a Group II oil. Which was a lot cheaper to produce, but which Castrol continued to sell as the same "synthetic" Syntec product. ExxonMobil didn't like this, since they'd been selling the more-expensive-to-produce PAO-based Mobil1 since the early '70s.

Eventually, ExxonMobil lost, and Castrol won the right to call Syntec (Group II) "synthetic", even though it is not based on a man-made molecule from ethane. Instead, it's catalyzed from mineral oil. Now, several mfgrs of "synthetic" oil are using Group II base stocks instead of PAO and (di)ester base stocks.

All of which is why I said, "synthetic oil" != "synthetic oil".

You can buy a good Group II oil from a major label (not labelled "synthetic") and get the benefits of very clean oil today, without paying very much more than a house brand Group I oil. Clean oil in this case means it starts out with a pH level that tends to remain neutral longer than non-clean oil. Oxidation rate is decreased when you start with complete molecules. Oxidation = acid in lube oil. Acid is not good in a crankcase, and encourages sludge formation. Chevron's Supreme, RPM, and (for trucks class engines) DELO lines all fall into this category, as does -- believe it or not -- Pennzoil these days, though not Quaker State for some reason.

You can spend more and get something labelled "synthetic" but that is still Group II oil and not based upon PAO tech. This may or may not be any better than just buying a good Group II oil.

You can buy a "real" Group IV PAO synthetic, such as Chevron's synthetic or Mobil1, and gain superior viscosity stability and further reduced oxidation resistance over a good Group II oil, as well as a wider overall viscosity range.

You can buy a premium synthetic Group IV oil, such as AMSOil (and perhaps Royal Purple etc.) and gain some other benefits, that I am not prepared to enumerate right now -- I just haven't done the research recently.

Other issues:"High Mileage" engine oil. Basically, it has more seal-swell agent to try to keep valve stem seals softer and leak less, after they've gone hard from hot shutdowns with no lube flowing to them. That's it, folks.

NAPA and Valvoline are Ashland Corp., same oil goes to both bottles. I used to really like Valvoline, but the independent testing I've seen of their recent stuff leaves something to be desired. I'm sticking with Chevron.

I could go into the way better oils far exceed the minimum API (US)/ILSAC(Europe)/JAMA(Asian) standards, versus just meeting them, but this has already grown too long.

So how do Chevron's group II oils stack up to other major brands - specifically Castrol GTX 20w50? My thinking being along the lines of Exxon in that Castrol really shouldn't be calling it synthetic if it isn't..... so maybe I would do better to support Chevron and use their 20w50 non-synth. I'm not a synth user, so I would like to hear your opinion on it. Although - I can imagine that if the presentation was put on by Chevron, then they probably made their junk out to be the bees knees..... but it sounds like you've done your fair share of research into this topic.... something I have no desire to do being just a simple software engineer, and far removed from the world of oil analysis.... any direction or background you could give would be much appreciated

A rose by any other name would smell as sweet, but "synthetic oil" != (does not equal) "synthetic oil".

Just this last week, I attended a 3.5 hour lecture on PCMO (Passenger Car Motor Oils) and a section on modern coolant issues, put on by ChevronTexaco and hosted by Bob Nehren, Chevron Lubricants Training Specialist -- Hey, they give me a free dinner to attend, and I won a Leatherman knock-off as a prize for knowing the answer to one of his rhetorcial questions, so why not?

I'm an oil snob, won't use just anything if I have a choice, and I tried to pay attention to the lecturer's info, because it does pay to know more about this sort of thing.

Some high points:

Synthetic oil is man-made. Man-made from what? Ethane, if I recall correctly. That would be C2H6, I think. That's synth. oil base stock, and for decades its adavantage over non-synth is that it is very, very clean. Lube oil from 20 years ago was about 70% clean. Really. That's as clean as they could make lube oil from mineral base stock and still sell a product economically. Synth oil tech was around (since WWII) but it was expensive to produce the stuff, too expensive to sell for cars.

"Synthetic" oil for cars uses (used, see below) Poly Alpha Olefin (PAO) technology to provide the major benefits to the synthetic base stock.

Some premium and aviation synth. oils use organic esters (diesters, polyol esters) instead of PAOs. AMSOil falls into this category. It's more expensive than PAO tech.

Until about 3/4 years ago, the term "synthetic" would refer to oil intended for cars that used either (di)ester or PAO tech in its formulation.

Refining process categories have been established by the American Petroleum Instute (API). A good overview is at Chevron's site. Broadly, they are:

. Group I
Solvent Extraction method of refining. This method removes 50-80% of the junk in conventional distilling of lubricating oil. It uses solvents in two stages to remove aromatics and waxes from the base stock.

. Group II
Hydroprocessing method of refining. Uses three stages, primarily high pressure catalytic (hydrocracking), to convert incomplete carbon molecules to complete molecules (no weak bonds?), converts waxes to isoparaffins (isodewaxing), and uses no solvents. End product is 98%+ clean, with almost no aromatics, nitrogen, sulpher, and little impurities.

. Group III
Unconventional base oils (UCBO), same as Group II except viscosity index (VI) is greater than 120. VI is "the resistance of an oil to viscosity change as temperature changes. The higher the VI, the more stable the viscosity over a wide temperature range. In other words, the higher the VI, the less an oil will thicken as it gets cold and the less it will thin out at higher temperatures—providing better lubricant performance at both temperature extremes." (Ref.)

. Group IV
Poly Alpha Olefins base -- see above. More expensive to produce than Group II/III, but less expensive to produce than (di)ester tech.

. Group V
Catch-all group. Everything else. This includes very cheesy oils, and also very high-quality oils including (di)esters.

BTW, Chevron invented modern hydrocracking/isodewaxing technology, and now 2/3rds of lubricating oil sold in the US uses their licensed refining technology.

Now.Group I oils is what we had for cars until about 1982 (except ATF, which has been a synthetic blend for over 40 years, I think). It's also what the cheap stuff you buy in Brand X (Say, Wal-Mart) bottles contains. About 70% clean, 80% from a the very best Group I refiners. Read the API "donut": do you see SL or CH-4 ratings? I didn't think so. Group I oil won't meet those specs even minimally.

Group II oils are the std oil that major brands -- all major brands -- are selling by 2004.

Group IV oils (synthetic, PAO) is what pretty much all volume "synthetic oil" used to be five years ago. ExxonMobil's Mobil1 is one example of a PAO Group IV synthetic.

Castrol was petitioned to an industry self-regulatory body by ExxonMobil over the use of the term "synthetic" several years ago, because Castrol's Syntec, which had been a PAO oil, was later changed to being a Group III oil. Which was a lot cheaper to produce, but which Castrol continued to sell as the same "synthetic" Syntec product. ExxonMobil didn't like this, since they'd been selling the more-expensive-to-produce PAO-based Mobil1 since the early '70s.

Eventually, ExxonMobil lost, and Castrol won the right to call Syntec (Group III) "synthetic", even though it is not based on a man-made molecule from ethane. Instead, it's catalyzed from mineral oil. Now, several mfgrs of "synthetic" oil are using Group II/III base stocks instead of PAO and (di)ester base stocks.

All of which is why I said, "synthetic oil" != "synthetic oil".

You can buy a good Group II oil from a major label (not labelled "synthetic") and get the benefits of very clean oil today, without paying very much more than a house brand Group I oil. Clean oil in this case means it starts out with a pH level that tends to remain neutral longer than non-clean oil. Oxidation rate is decreased when you start with complete molecules. Oxidation = acid in lube oil. Acid is not good in a crankcase, and encourages sludge formation. Chevron's Supreme, RPM, and (for trucks class engines) DELO lines all fall into this category, as does -- believe it or not -- Pennzoil these days, though not Quaker State for some reason.

You can spend more and get something labelled "synthetic" but that is still Group II or III oil and not based upon PAO tech. This may or may not be any better than just buying a good Group II oil.

You can buy a "real" Group IV PAO synthetic, such as Chevron's synthetic or Mobil1, and gain superior viscosity stability and further reduced oxidation resistance over a good Group II oil, as well as a wider overall viscosity range.

You can buy a premium synthetic Group IV oil, such as AMSOil (and perhaps Royal Purple etc.) and gain some other benefits, that I am not prepared to enumerate right now -- I just haven't done the research recently.

Other issues:"High Mileage" engine oil. Basically, it has more seal-swell agent to try to keep valve stem seals softer and leak less, after they've gone hard from hot shutdowns with no lube flowing to them. That's it, folks.

NAPA and Valvoline are Ashland Corp., same oil goes to both bottles. I used to really like Valvoline, but the independent testing I've seen of their recent stuff leaves something to be desired. I'm sticking with Chevron.

I could go into the way better oils far exceed the minimum API (US)/ILSAC(Europe)/JAMA(Asian) standards, versus just meeting them, but this has already grown too long.

Originally posted by GeneralDisorder So how do Chevron's group II oils stack up to other major brands - specifically Castrol GTX 20w50?

I don't have data for Castrol, other than a couple of histograms provided by ChevronTexaco, on acid stability index or something (the datasheets are not right here, I've got them at work, so I've been reading off of last year's presentation materials). And, as you say . . .

. . . the presentation was put on by Chevron, then they probably made their junk out to be the bees knees.....

Just so. No way is the presenter going to say, "Well, our product scored an impressive 3rd place in this test, but we really feel it's the best in class!" Just isn't going to happen. The presenter isn't objective. The API/ILSAC/JAMA guidelines are minimum requirements for lubricating oils for certain specific applications, but Chevron presented data that showed that while "C", "V", "P", and "Q" all met various specs, Chevron's subject product far exceeded the spec in certain performance tests. However, there are a lot of tests, and I only saw results for two: the two where Chevron's product shined, probably.

Still, ChevronTexaco is the pioneer in hydrocracking/isodewaxing technology, and it is a logical assumption to conclude that they just may know how to get more out of a refining process than other licensees of their technology.

My thinking being along the lines of Exxon in that Castrol really shouldn't be calling it synthetic if it isn't.....

Ah, but the regulatory body (self-regulatory, that is: it's a non-governmental organization, if I understand correctly) said that Group III oils are sufficiently changed by the process as to be considered "synthetic". It's just that, for you & me, there are now three distinct categories of "synthetic": Group II/III, PAO, (di)ester. Mondo confusing.

ExxonMobil has stated that their product uses PAO base stock. It's widely available and priced competitively with Syntec.

so maybe I would do better to support Chevron and use their 20w50 non-synth.

Just for fun, on the Aerostar (3.0l V6) that I've been running Syntec, then Mobil1 in for 40k miles, this last oil change I put in Chevron 20W50 non-synth. Exactly when I changed to it, I now get about one second of what sounds like lifter noise in the morning, though with that short period it is almost certainly bearing noise, and for the first time ever, I get occasional visible smoke in the rear view mirror if I floor it, which I never got from the old (PAO) Syntec 5W50 or Mobil1 10W30.

Next oil change, I'm going back to Mobil1, with its low volitility rate (does not burn as easily) and low pour point (flows better cold).

I'm not a synth user, so I would like to hear your opinion on it.

I had a bad experience with Mobil1 in about 1975 with some specialty engines, two of them, and I shied away from synthetics for many years afterward, except for some dabbling with AMSOil in the early 80s.

In 1994, I bought my father's '83 Chev G30 (1T van) with the first-production-year 6.2l diesel -- a model which later proved to have a few teething problems like leaky head gaskets, none of which exhibited on my rig. I got it at 102k. Dad is a maintenance "freak", but he ran only GM oil. That is, he bought the oil from GM!

I switched it to the then-new Syntec 5W50, which is not a diesel-rated lubricant.

When I bought the van, it got 18 MPG, and used a quart of oil in 800 miles. When I sold it seven years later, at 180k miles, it had a 78k miles average of 19.2 MPG and was using a quart of Syntec in 1800 miles, and still leaked not at all, still ran very well. To my knowledge, it is still pulling around a horse trailer in Bellingham or Blaine, Wash.

I have similar stories to tell about two other vehicles I bought used and switched to the old (PAO) Syntec.

However, this Aerostar's oil consumption went up a couple of years ago, and I was perplexed about it until the news of Syntec's reformulation hit the news. Then it made sense.

I like good oil, but I'm not a fanatic about it. Clean is best, and anything you can do to keep it clean is probably going to be the best course. Even ester oil will not do you much good if you run it for 10k miles with conventional fuel and filtering.

This is by way of explaining why I don't run the best oil available (which may be AMSOil for most people; there are competing products that might be "as good", but I hesitate to even name them here, because I'm just not sure yet.) The economics of keeping a modern car usable do not mandate that I double the cost of an oil change, and extending the drain intervals isn't a good idea unless you either change the fuel (to LPG or CNG) or change the filtering (to something that can filter under one micron, like AMSOil's excellent full/bypass dual filter setup). If you don't keep the suspended particles concentration low, I don't care how "good" the oil is, it can't compensate for the sandpaper effect.

Sorry I can't say more on Castrol's non-Syntec products. I liked Syntec when it was PAO, and I ran 20W50 GTX for years in my air-cooled VWs, but for various reasons I don't use Castrol products today.

BTW: do not, under any circumstances, use an engine oil additive containing PTFE ("Teflon"). Dupont, the "Teflon" trademark owner, long ago firmly disassociated themselves with any claims related to putting PTFE into a crankcase, and many tests by independent labs have confirmed that PTFE does absolutely nothing for an engine, when PTFE particles are introduced in crankcase oils. Examples of PTFE-carrying additives include Slick-50 (useless, so useless that the new buyer of the old Slick-50 company advertises it not at all and makes absolutely no claims to its effectiveness!) and I believe ProLong.

"Synthectic Blend" means squat. There is no regulatory body that prescribes a minimum amount of "synthetic" oil that must be present in a "blend". Don't bother, you almost certainly won't get enough of the good stuff in a "blend" to make it worthwhile.

"Detergents". The ChevronTexaco presenter made a point that I knew about, but he did it in a way I thought was memorable. He was talking about the various properties that a lubricating oil must have, and the various additives that go into a lubricating oil to achieve those properties. He was going down a list, and came to "detergents". He said, "In english, the word 'detergent' means one thing in oil and another in the rest of the world. When you hear the word, 'detergent', what do you think of?" The audience mostly mumbled, "Tide". "Right. Now, repeat after me: oil detergents are not like Tide!

Oil detergents work like this: they find a piece of clean metal. They stick to it. When a varnish molecule goes floating around, it looks for clean metal to bond with, but finds no room at the inn, because the detergents molecule is coating it already.

IOW, high-detergent oil does NOT clean a dirty engine like Tide! Some varnish or sludge may become loosened from normal agitation or the regular washing properties of the additive package, get suspended in the oil and removed during an oil change, but in general, switching to an oil that has a high detergent package will not significantly clean an engine. Detergents reduce the formation of deposits.

One AMSOil dealer's website implies otherwise for their engine flush product, stating that that product's main ingredient is a concentrated form of what is in the AMSOil oil. I don't know if AMSOil's detergent package is different that anybody else's, so for this one I'm just passing it along.

A pretty funny (and as far as I have read, accurate) account of the state of synthetic motor oils as of 2000, by Patrick Bedard, contributor to Car & Driver:http://www.texassynt...rolmobilpao.htm

Late in 1997, Castrol changed the formula of its Syntec "full synthetic motor oil", eliminating the polyalphaolefin (PAO) base stock (that's the "synthetic" part, which makes up about 70% by volume of what's in the bottle) and replacing it with a "hydroisomerized" petroleum base stock.

Mobil Oil Corporation, maker of Mobil 1, "Worlds Leading Synthetic Motor Oil," said no fair and took its complaint to the National Advertising Division (NAD) of the Council of Better Business Bureaus. [snip] In the end, NAD decided that the evidence constitutes a reasonable basis for the claim that Castrol Syntec, as currently formulated, is a synthetic motor oil, said Lubricants World.

Lubes'N'Greases, Jul. 2001. 2 pages."... a 1999 ruling by the National Advertising Division of the Better Business Bureaus broadened the definition of synthetic lubricants to include Group III base stocks. With Group III granted the right to wear the Œsynthetic label -_ and a cost differential of $1.50 to $2.00 a gallon in favor of Group III _ most large lubricant producers moved quickly to replace PAO with Group III in their synthetic PCMO formulations."

[edit]I had some spare time today, started reading the Chevron Salefax Digest. It seems that there are two synthetic motor oils from Chevron:

Chevron Supreme Synthetic (for cars) Available in several grades: 5W30, 10W30, and 5W40 at least.

The Delo product has additional soot dispersal capability, but the total ash content is within 0.1% of the Supreme product.

Now the really interesting stuff.I called the Chevron tech support number. I was told that there are five, ful-time guys answering oil Qs there. I asked point blank if the either the Supreme or Delo synthetics were PAO or Group III. The guy didn't know off the top of his head, but after I'd qualified myself as an attendee to one of Bob Nehren's lube seminars, he spent a minute looking it up. After some page turning, he told me that the majority of the base stock for Supreme is Group III. OK, I said, what about the Delo synthetic? More page-turning, then the same answer.

So, there you have it: Chevron's synthetic is a highly-refined paraffinic/mineral oil base. Just like Castrol. A pretty good oil, but not (to my thinking) a "real" synthetic.

One could infer that the large markup/low base price of your Valvoline product implies that it does not contain PAOs. IOW, it's a Group III base stock. Maybe better than a Group II oil. Is the cost of it getting you a significan't benefit over Valvoline's standard oil? I don't know.

Since Group II oils from major mfgrs is 98%+ clean nowadays, and that's the same for Group III oils, the only advantage of a non-PAO "synthetic" is a possilby higher VI (longer/wider viscosity stability) than Group II. You aren't getting PAO or ester tech, and you don't really know what is in the bottle anyway -- a mix of base stocks is now very common.

If you find some web reference to shed some light on "V"'s or "C"'s synthetic mix, please post it. I'd be interested.

Originally posted by subyluvr2212 Ran the same partial synth in XT. Due to results from Legacy, switched back to dino. Oil pressure went up 2-3 lbs.

"Partial synthetic" is sorta like "genuine gold-plated". It's a blend of something Valvoline calls synthetic (which might be a Group II/III oil, or it could be a PAO oil) but you don't know which. And it's anybody's guess as to how much "synthetic" oil they put in the bottle. IOW, a rip-off.

You could see 2-3 lbs oil pressure difference between a rainy day and a sunny day.

You mineral oil may be a better oil than the synthetic blend. A good Group II oil can have lower NOACK volitility than a sh*tty synthetic blend. But I have no numbers to back that up.

Unrelated: I ran across this pic of a Forester with a dual-bypass filter setup.

It looks like there is an oil/water heat exchanger on there too. Kind of a dumb question, but is that OEM on the forester? I have never heard of them coming from the factory with one of those. It looks like a very clean installation. Notice the thermostat housing has a coolant pipe on it going to the heat exchanger. Interesting.

Amsoil ATM and ASL (I use both) are group IV PAO based, btw. With my preferred customer discount I get them for $4.55 a quart. Very good PAO oils IMHO.

There are alot of differences between the JDM WRX and USDM WRX. As well as the STi....the main one being the EJ207 is used for JDM and the rest of the world, but the USDM gets the EJ257. The WRX in both cases get the EJ205. BOth of them used ot get the same engine in Japan, but that changed with the GD*/GG* chassis.